The question is, could you comment on the content of the prayer. Specifically:
- we ask God that his will be done, as if alternatives to his will could be done instead;
- we link our works of forgiveness to the forgiveness of our sin;
- we ask God to not tempt (or test) us;
- we ask God to liberate us from the Devil.
All these pose no difficulty for me as a Catholic to be understood straighforwardly:
- I normally do what I will, which may or may not conform with God's will;
- my salvation is predicated on my works of charity;
- my faith is tested by events and may be damaged or extinguished;
- despite the acknowledgement of my faith inherent in the prayer, I may lose my salvation to Satan.
Additionally, if you look at the actual Matthew 6:11, it differs from the traditional wording of the prayer as the bread is described as "supersubstantial", -- "epiousion", another (with "kecharitomene") unique word formation that refers to the transsubstantiated bread of the Eucharist rather than the gastronomical bread.
I was wondering how a Calvinist would explain these things.